Steven Crane Compiled Section Handouts. Human Behavioral Biology 2012

antidepressant. Interpretation: depression is in some way about psychic pain.

How does the brain react to the trolly problem? How about when the judge instructs a jury?

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  The frontal cortex decides to pull the lever
  
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  The limbic system decides to not push the person
  
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  Judge: "we all have feelings for those with horrible luck in life but remember your job is to simply decide whether or not a law was broken. Ignore your feelings." condition 1.
  

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  Activates frontal cortex
  

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  Judge: "laws are great, but it's about protecting the weak from the mighty." condition 2.
  

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  Activates limbic structures
  

Finally, what do the hypothalamus, midbrain, and brainstem regions have to do with aggression?

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  Highly active during aggression.
  
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  But it turns out that's just for any general state of arousal. Including orgasm etc.
  
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  (Same story with arousal hormones: epinephrine). Opposite of love is not hate; opposite of love is indifference.
  

Aggression II
Neurochemistry of aggression (seconds before the aggressive behavior)

What is the driving force giving your frontal cortex the power to do the harder but right thing?

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  Dopamine
  

Serotonin time

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  What are low levels of serotonin associated with?
  

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  Impulsive behavior. Impulsive aggression.
  

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  How does serotonin synthesis inform our understanding of its role in aggression?
  

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  Serotonin is made from tryptophan. The enzyme that does this conversion is TH.
  
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  When serotonin acts in a synapse, it is then either reuptaken or degraded by MAOb, an enzyme.
  
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  So these actually contradict the "serotonin = impulsive aggression" story. How so?
  
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    Poor MAOb variant means more serotonin will act in the synapse. But people with this variant have